HARIPRASAD, K.V.UMADEVI, G.M.2019-05-022019-05-022018http://krishikosh.egranth.ac.in/handle/1/5810101680D5711The present study entitled “Studies on preference of Callosobruchus maculatus Linnaeus on various chickpea varieties and its management with edible oils” was carried out under laboratory conditions at the Department of Entomology, S. V. Agricultural College, Tirupati during the year 2017-18. The performance of 16 chickpea genotypes was assessed based on the biological parameters of the test insect and seed damage. The genotypes NBeG-49 and NBeG-47 which recorded index of susceptibility (IS) of 0.9 and 1.3 were categorized as resistant genotypes, while seven genotypes viz., Vihar, NBeG-3, NBeG-119, NBeG-511, JAKI-9218, NBeG-452 and ICCV-2 with the index of susceptibility (IS) ranging between 4.3 to 6.7 as moderately resistant to the bruchid attack and the rest of the seven genotypes viz., NBeG-458, NBeG-399, JG-11, NBeG- 471, NBeG-507, ICCV-2 and NBeG-732 with the index of susceptibility (IS) ranging between 7.6 to 8.7 as susceptible genotypes against C. maculatus. The germination percentage of infested seeds of 16 chickpea genotypes were significantly different from each other. The genotypes with less infestation recorded highest germination percentage (96.67%) over the heavily infested seeds (23.33 %) which recorded less germination percentage. Among the various physical parameters, colour, size and surface texture of the seed played a major role on the oviposition preference of the test insect. The varieties with creamy white colour and tuberculated smooth textured were preferred more for xiv oviposition than the brown colour and rough surface seed. The length of seed, width of seed and test weight of seed had influence on per cent infestation of the test genotypes. The chemical constituents such as low aminoacids, carbohydrates and proteins of the test genotypes were detrimental to the growth and development of the bruchids. The genotypes with differential reaction had affected the biology of test insect. The resistant genotypes NBeG-49 and NBeG-47 recorded lowest number of eggs, less per cent adult emergence, less mean development period and growth index over the susceptible genotypes NBeG-458, NBeG-399 and JG-11.The moderately resistant genotypes Vihar and NBeG-3 were intermediate in between resistant and susceptible genotypes. Ovipositional preference of C. maculatus on selected genotypes of chickpea under free choice condition varied significantly. The genotypes JG-11 (9.67 %), NBeG-458 (11.00 %) and NBeG-399 (12.00 %) recorded more number of eggs over NBeG-49 (3.33 %) and NBeG-47 (5.00 %). The genotypes Vihar (8.67 %) and NBeG-3 (8.00 %) were intermediate in position. The edible oils used in the study indicated that all the oils viz., groundnut, mustard, sesamum, olive, rice bran and sunflower were effective at 1ml/100g seed concentration which recorded less number of eggs, less per cent adult emergence, MDP (mean development period) and high oviposition inhibition percentage. Among them groundnut and mustard oils were effective at 0.5ml/100g seed. The oils and concentration levels had effect on seed germination. All the oils were recorded less germination percentage over control (70.00 %). There was no significant difference between the oils with respect to germination percentage of seeds.en-USnullThesis